Hydraulic pumping oil unit can take the maximize advantage of the productivity of oil wells in oil exploitation, full of energy conservation, and has been attached great importance to domestic and foreign oilfield engineering technical personnel. Along with the hydraulic technology improved, the hydraulic pumping unit was developed rapidly, and was applied in oilfield production with certain amount. The development of hydraulic pumping unit was studied systematically with comprehension in aspects of structure, control and matched weight at home and abroad in recent 5 years. It is discussed of existing problems and the required direction of further study of the hydraulic pumping unit. 